Heat transfer is always a critical problem for electronic devices. In order to facilitate the operation of the electronic device, heat generated by the internal components, such as electrical circuitry or processor, should be transferred and removed quickly. Recently, electronic devices have been designed to be as thin as possible, leaving very small and narrow gaps between the outer case and internal components of the electronic devices. As such, the air trapped in these gaps becomes a heat transfer barrier and prevents the heat from dissipating to the environment due to the poor heat conductivity of air. Consequently, the heat generated by and accumulated on the internal components of the electronic devices not only reduces the processing speed, but sometimes also causes damage to the chips or processors within the electronic devices.
One known solution is directly attaching a solid metal plate, such as copper or aluminum, to the chip or processor of the electronic devices. The attachment of the metal plate may enhance the heat conduction from the attached electronic component, but could only direct the heat generated by that single component without influencing other heat sources that are not in direct contact with the metal plate. In order to conduct the heat away from different electronic components, each component should be attached with its own heat dissipation plate. Such arrangement not only increases the weight of the electronic device, but also raises the cost of material, as some metal plates with good heat conduction property are expensive.
Another known solution is to seal the outer case of the electronic devices air-tight by filling the gas coolant within the enclosed space. However, the process of forming an air-tight compartment for electronic devices is not economical. Further, the gas coolant will eventually leak away from the case over time, and the replaced air occupying the compartment will lead to the same result of heat transfer barrier.
Further, in a solution that a fan is mounted at the vent opened on the outer case for creating compulsive convection, the air flow may only achieve nice circulation at a limited local area around the vent. If the heat sources are disposed far away from the vent, the air flow around the vent created by the fan cannot take away heat generated by the heat sources easily, and more power is needed for the fan to draw the heat away from the heat sources.
Therefore, a need exist for effectively and continuously removing heat from the electronic devices in a cost effective manner.